io6 



MANUAL OF ZOOLOGY 



Fig. 48. — Physalia. The living animal 

 floating on the surface of the sea. cr, 

 crest ; p, polype ; fin , pneumatophore, 

 float, or air-sac. (After Huxley.) 



Fig. 49. — Physalia arethusa t natural 

 size. (After Agassiz.) 



